There was some miscommunication on things. Saw a lot of them after I posted. No more than 4 units per player; beginning of round (the defender may target not you). Smaller games will struggle to have late game deploys and the large games deploying slower was the initial point. You will be pushed to only have a few units at first and use them to actually start the fight. Since the defender can only attack after the alarm is released it's their job to raise it (hopefully turn 1) otherwise the attacker could pick off all the sentries.